Real World NAT64 deployments

Mark Andrews marka at
Thu Mar 3 19:16:59 CST 2011

In message <AANLkTinvcmuL_M0bEBCuN-_zunAYFCe1PNsNW9FceJ-0 at>, Will
iam Herrin writes:
> On Thu, Mar 3, 2011 at 5:01 PM, Hammer <bhmccie at> wrote:
> > A little better. So what's the difference between 6to4 and 6in4?
> Isn't 6in4 what HE uses?
> I haven't used 6in4 so I couldn't tell you.
> 6to4 is a stateless tunnelling protocol. You have a dual-stacked
> router. It has an IPv4 address, Therefore it supports a 6to4
> IPv6 network numbered 2002:0102:0304::/48. Somebody tries to send a
> packet to 2002:0102:0304::1, it goes to a 6to4 router which
> encapsulates the IPv6 packet in an IPv4 packet and sends it to
> 6to4 is handy as a toy or for experimenting, but it relies on a loose
> network of generous volunteers who, while generous, are neither
> generous nor numerous enough to support production traffic.

Any ISP that is delivering IPv6 to their clients would be insane
to not run a 6to4 relays for return traffic to 2002::/16.

Mark Andrews, ISC
1 Seymour St., Dundas Valley, NSW 2117, Australia
PHONE: +61 2 9871 4742                 INTERNET: marka at

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